Formada3D NFT channel end caps, O-ring sealed, for 100 x 50 rectangular downpipe or 90 mm pipe (blank, low port or centre port)
Slip-over end caps for nutrient-film (NFT) hydroponic channels made from Australian 100 x 50 mm rectangular downpipe or DN90 round stormwater pipe. The seal is a replaceable 3.5 mm O-ring in an internal groove that squeezes onto the outside of the channel, so there is no silicone and nothing to glue. Three versions in each size: blank, a low port (drain end) and a centre port (inlet or mini float valve); the ports take a standard 1/2 inch BSP tank connector, bulkhead or float valve, with no printed threads to strip. One 90 x 3.5 mm O-ring fits both sizes. Black PETG, printed to order in our Melbourne workshop.
From A$8 for the single end cap. Printed to order in Melbourne and shipped Australia-wide; we confirm the final price and lead time before anything is printed.
On the quote page choose Request a quote (no file needed) and name this part and the option you want.
Order status. DN90 round caps are sized from the pipe maker's published outside diameter. Rectangular downpipe makers publish only the nominal 100 x 50 size, so the 100 x 50 caps come with the free fit coupon (steel and PVC downpipe can differ). The O-ring seal is a design feature, not a pressure or IP rating; check for leaks over a tray before you rely on it.
What does it look like in use?
Renders are computer images of our own design, made from the same model we print. This family is made to order: real photos of our first prints are coming.
Specifications: material, size and what it fits
| Spec | Detail |
|---|---|
| Material | PETG (black), 0.24 mm layers on a 0.6 mm nozzle, 5 walls, 15 % gyroid, no supports, end wall on the bed |
| Sizes | 100 x 50 cap 109 x 59 x 26 mm (about 38 g); DN90 cap 99 x 99 x 26 mm (about 41 g) |
| Seal | Internal groove for a 3.5 mm section O-ring: 22 % radial squeeze at 0.30 mm clearance, groove 4.8 mm wide with a 45-degree roof. One 90 x 3.5 mm NBR O-ring fits both sizes, or 3.5 mm O-ring cord cut to 293 mm and joined |
| Ports | Low port: 21.5 mm hole, centre 17 mm above the outside bottom (drain end). Centre port: inlet or mini float valve. Both take a 1/2 inch BSP (ISO 228-1) tank connector, bulkhead or float valve |
| Fits | DN90 PVC stormwater pipe (90.0 mm outside, from Iplex's published size guide) and nominal 100 x 50 mm rectangular downpipe (steel or PVC; nominal size from the makers' catalogues, exact outside size and corner radius not published) |
| Not included | O-ring, tank connector / bulkhead / float valve, channel |
| Fit coupon | Free with an order for the 100 x 50 size: three frames at 0.20 / 0.30 / 0.45 mm per side. Slide each over your downpipe and we print the caps at the one with a light drag |
How much does it cost?
Guide prices for printed parts, in Australian dollars. Shipping is extra; we confirm the final price, including any business minimum, before printing. Bulk and custom sizes are quoted per job.
| Option | From |
|---|---|
| Single end cap (blank, low port or centre port) | A$8 |
| Pair of end caps (any two), 100 x 50 | A$15.95 |
| Pair of end caps (any two), DN90 | A$15.95 |
| 100 x 50 fit coupon | Free with an order |
Who it's for
NFT and DIY hydroponic growers building channels from downpipe or stormwater pipe, and schools and community gardens running small NFT systems.
Safety & use
Installation & use. Designed for the uses described on this page only. Fixings are not included: use the sizes listed, check they are tight before use, and check the parts regularly for wear or damage. Not for safety-critical or overhead load-bearing use. Damage caused by misuse, modification or overloading isn't a fault in the product.
Water and food. PETG is not a certified food-contact material, and no printed part carries a food-safety certification. Indoor or shaded use; replace a part that turns cloudy, chalky or cracked. Rinse and clean with mild detergent or dilute hydrogen peroxide, not a dishwasher.
Leaks. Not pressure rated and not leak rated: an O-ring sealed design for open NFT channels at low head. Fill the channel and check it over a tray or paper towel for a day before leaving it unattended.
This doesn't affect your rights under the Australian Consumer Law.
Common questions
Which channels do they fit?
Australian 100 x 50 mm rectangular downpipe (steel or PVC) and DN90 round PVC stormwater pipe (90 mm outside). For 100 x 50 the exact outside size is not published, so a free fit coupon comes first.
How do they seal?
A standard 3.5 mm O-ring sits in a groove inside the cap and squeezes onto the outside of the channel about 22 %. One 90 x 3.5 mm NBR O-ring fits both sizes, or cut 3.5 mm O-ring cord to 293 mm and join it. No silicone, and the seal can be replaced.
Which fittings go in the ports?
A standard 1/2 inch BSP tank connector, bulkhead or mini float valve through the 21.5 mm hole. The low port drains the channel; the centre port suits an inlet or float valve. Fittings and O-rings are not included.
Are they watertight?
They are an O-ring sealed design for open NFT channels at low head, not pressure rated and not tested to an IP rating. Fill the channel and check for leaks over a tray before relying on it.
How do I order?
Use Get a quote and choose Request a quote, naming the size (100 x 50 or DN90), the versions (blank, low port, centre port) and the quantity. We confirm the price and lead time before anything is printed.
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Last updated 15 October 2026.